The Cerebrum

Largest and most conspicuous part of the human brain.

 

  

 

 

 

 

 

Cerebral medulla

Most of cerebrum is white matter.

Consists of nerve fibers conducting signals from one region of the cerebrum to another and between the cerebrum and lower brain centers.

 

Cerebral cortex

Neural integration is carried out in the gray matter of the cerebrum.

 

Basal nuclei

The basal nuclei are clusters of gray matter found deep within the cerebral medulla

The three pair of basal nuclei are

• caudate nucleus
• putamen
• globus pallidus

 

 

 

Limbic system

Series of interconnected rings that are an important center of emotion and learning.

 

 

Higher Forebrain Functions

Primary cortex

regions that receive input directly from the sense organs or brainstem, or issue motor commands directly to the brainstem for distribution to the cranial and spinal nerves.

Primary Somesthetic (Somatosensory) Cortex

Located on the anterior edge of the parietal lobe

Functions in the interpretation of the sensation of touch from areas of the body

Primary Motor Cortex

Located on the posterior edge of the frontal lobe

Functions in the initiation of skeletal muscle contractions

This is where we plan our behavior

 

Association cortex

Consists of all regions other than the primary cortex, involved in integrative functions.

75% of the mass of the cerebral cortex is association cortex.

 

Motor Control

Upper motor neurons

These tract decussate (cross from one side of the body to the other) in the pyramids of the medulla oblongata and then continue into the spinal cord.

Lower motor neurons

The fibers from the upper motor neurons synapse with the lower motor neurons whose axons innervate the skeletal muscle.

 

Other areas of the brain important for muscle control

Basal nuclei

The basal nuclei assume control of highly practiced behaviors that one carries out with little thought - writing, typing, driving a car, etc.

Cerebellum

Highly important in motor coordination

Aids in learning motor skills

Maintains muscle tone and posture as well as smooth muscle contractions

Coordinates eye and body movements

Coordinates the motions of different joints with each other

 

 

Language

Includes several abilities - reading, writing, speaking and understanding spoken and printed words

Assigned to different regions of the cerebral cortex

 

 Emotion

Result from an interaction between areas of the prefrontal cortex and the diencephalon

The hypothalamus and amygdala play especially important roles in emotion

 

 

Cognition

Acquisition and use of knowledge - sensory perception, thought, reasoning, judgment, memory, imagination, and intuition.

The prefrontal cortex is concerned with many of our most distinctive abilities, such as abstract thought, foresight, judgment, responsibility, a sense of purpose and a sense of socially appropriate behavior.

Cerebral lateralization

• in women, the left temporal lobe is longer than the right
• In left-handed people, the left frontal, parietal and occipital lobes are usually wider than those on the right
• the two hemispheres are also different in some of their functions
• Neither hemisphere is "dominant" but each is specialized for certain tasks

  

Are You Right or Left Brained? Take the Quiz.

 

Here is another quiz.

 

 

 

  

 

  

 

 

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